Outer rotor type motor

Abstract

An outer rotor type motor includes a rotation shaft installed in a bearing housing; a stator formed of a field winding; a rotor disposed outside the stator to house the stator and having a yoke surface on which a permanent magnet for performing a magnetic interaction with the field winding of the stator, the rotor rotating around the stator; and a shaft bushing for connecting the rotor and the rotation shaft. The shaft bushing is insert-molded at a central portion of the rotor to be connected with the rotor.

1 . An outer rotor type motor comprising: 
 a rotation shaft installed in a bearing housing;    a stator formed of a field winding;    a rotor disposed outside the stator to house the stator, and having a yoke surface on which a permanent magnet for performing a magnetic interaction with the field winding of the stator, the rotor rotating around the stator; and    a shaft bushing for connecting the rotor and the rotation shaft,    wherein the shaft bushing is insert-molded at a central portion of the rotor to be connected with the rotor.    
   
   
       2 . The motor of  claim 1 , wherein the shaft bushing includes: 
 an engagement hole provided with a serration to be engaged with the shaft;    reinforcing ribs radially extended from an outer peripheral surface of the engagement hole;    an insert portion to be insert-molded with the rotor while forming bottom surfaces of the reinforcing ribs; and    an engagement groove vertically formed in a sidewall of the engagement hole starting from a bottom surface of the insert portion.    
   
   
       3 . The motor of  claim 1 , wherein the shaft bushing includes: 
 an engagement hole provided with a serration to be engaged with the shaft;    reinforcing ribs radially extended from an outer peripheral surface of the engagement hole;    an insert portion to be insert-molded with the rotor while forming bottom surfaces of the reinforcing ribs;    a stepped portion formed by cutting a lower portion of the engagement hole starting from a bottom surface of the insert portion; and    an engagement portion molded as one body with the insert portion and the stepped portion from beneath the rotor.    
   
   
       4 . The motor of  claim 2 , wherein an engagement boss to be press-fitted into the engagement groove is protrudingly formed at a position corresponding to the engagement groove in a central portion of the rotor.  
   
   
       5 . The motor of  claim 3 , wherein an engagement boss to be vertically fitted to the stepped portion is protrudingly formed at a position corresponding to the stepped portion in a central portion of the rotor.